This proposal requests funds to purchase a Zeiss LSM 710 Laser Scanning Confocal Microscope for a group of 8 NIH funded major users and 5 minor users in the Department of Neurology, the Alzheimer's Center and the Neuroscience Institute at Northwestern University Feinberg School of Medicine. These investigators are conducting studies of cerebral cortex development and connectivity, synaptic plasticity, stem cell biology, cellular mechanisms of dementia, multiple sclerosis pathogenesis, molecular basis of hearing and somatic sensation and retinal physiology. Their projects are heavily reliant on confocal microscopy for optical sectioning of thick tissues, co-localization and spectral separation of multiple fluorophores in mouse and postmortem human tissue. Additional applications include live imaging of retina and cochlea organotypic preparations as well as brain slices. At present, there are two confocal microscopes available to the entire research community at large on the Medical School campus of Northwestern University. These microscopes are so heavily used that reservations for sessions longer than 2 hours are frequently required weeks ahead. The upright Zeiss LSM 710 is a state-of-the-art instrument with outstanding sensitivity and sophisticated spectral imaging capabilities for separation of multiple fluorophores and tissue auto-fluorescence. The new microscope will be housed in a location central to the 8 investigators. Training, administration and billing will be managed by the Cell Imaging Core which is directed by a full-time imaging specialist at the rank of Research Associate Professor. An advisory committee will be formed to oversee the management and equitable operation of the equipment. The University has committed funds to refurbish a room for the microscope, purchase service contracts and help maintain the equipment through the Cell Imaging core. This new system would greatly relieve the current usage on the existing microscopes and allow this group of investigators sufficient confocal access to expedite completion of their NIH-funded projects and to advance their research in directions previously unfeasible.